Resources available at the Montréal Botanical Garden Through the Botanical Garden, Montréal has all kinds of resources available on environmentally friendly gardening. • Consult the Green Pages of the Montréal Botanical Garden Website. You’ll find a number of fact sheets on insect pests and diseases and all kinds of tips for maintaining your lawn, garden and indoor plants. ville.montreal.qc.ca/jardin/en/biblio/carnet • Come talk to the experts at the horticultural information counter in the Montréal Botanical Garden Reception Centre. Hours are posted on the Botanical Garden Website. Bring samples of diseased or infested plants. • Send in your questions by e-mail to the Botanical Garden Website, LOW-IMPACT by mail (to 4101, rue Sherbrooke Est, Montréal, Quebec, H1X 2B2) or by fax (514 872-3765). PESTICIDES On the Web • For more details on the Montréal By-law concerning pesticide use, the Clean Home and Green Garden – Guide to healthy home maintenance and ecological gardening , etc: ville.montreal.qc.ca/pesticides • Ministère du Développement durable, de l’Environnement Getting to know low-impact pesticides Think prevention et des Parcs ( Pesticides Management Code , alternatives first to pesticides, etc.): Although Montréal has a by-law prohibiting the outdoor use of pesticides, certain low-impact pesticides may be used mddep.gouv.qc.ca/pesticides/permis/code-gestion-en The best way to keep your at all times. Their active ingredients are considered to have low toxicity for human health and the environment. garden healthy is to choose • Pest Management Regulatory Agency (approval of pesticides): This brochure contains information on twelve active ingredients used in making low-impact pesticides, how they work, resistant plants suited to their pmra-arla.gc.ca growing conditions and to their targets, how to apply them and, of course, what precautions you should take when using them. maintain them properly Further reading (use compost, mulch, natural fertilizers, etc.). If insect pests, • Direction de l’environnement de la Ville de Montréal. 2006. diseases or weeds do appear Clean Home and Green Garden – Guide to healthy home despite your best efforts, try to maintenance and ecological gardening . Montréal, 36 p. What is a pesticide? At a glance take an environmentally friendly • Rubin, Carole. 1989. How to get your lawn & garden off drugs: approach: picking them off Pesticide-free gardening for a healthier environment . Ottawa: A pesticide is a natural or synthetic substance for controlling or The following table lists 12 active ingredients in low-impact or digging them out by hand, Friends of the Earth. destroying any undesirable organism. pesticides approved for household use in Canada. The details found here are for information only – always check the label pruning, using traps, etc. Synthetic or “chemical” pesticides contain organic compounds You should turn to low-impact • Harris, Marjorie. 1996. Ecological Gardening: Your Path to a on any product before using it and be sure to properly identify Healthy Garden . Toronto: Random House. produced in a laboratory. Natural pesticides are derived from the problem so that you can choose the right product. pesticides only as a last resort, when micro-organisms (bacteria, fungi, viruses, etc.), from plant, animal all other methods have failed. • Nancarrow, Loren and Taylor, Janet Hogan. 2000. Dead Daisies or mineral sources. Watch out, though. “Natural” doesn’t necessarily Make Me Crazy: Garden Solutions without Chemical Pollution . mean safe! Snake venom is natural, too, but some snake bites can Ten Speed Press. be poisonous or even fatal. Precautions • Schultz, Warren. 1989. The Chemical-Free Lawn . Emmaus, • It is best to wear gloves, goggles, long sleeves and pants and Pennsylvania: Rodale Press. 194 p. a mask when preparing and applying pesticides. Low-impact pesticides • If you suspect that a plant is sensitive to a particular pesticide, Low-impact pesticides have low toxicity for human health and the test it on a few leaves first and wait 24 to 48 hours, watching environment. They usually have little effect on organisms other than for signs of phytotoxicity (discoloured, spotted or dropped leaves, Regulations and by-laws those they specifically target, break down quickly and are unlikely etc.). Do not treat the plant if such symptoms appear. to cause target species to develop resistance. Authority to regulate pesticide usage in Canada is shared by • Avoid applying pesticides on windy days, to minimize drifting. the federal and provincial governments and municipalities. • Do not use pesticides near any body of water or wetland, or dump The provinces and territories may regulate the sale, use, storage, any pesticide or rinse your equipment near or into any bodies of transportation and disposal of pesticides approved by Health Active ingredients water, wetlands or sewers, as this will contaminate the water. Canada’s Pest Management Regulatory Agency (PMRA). They may also restrict or prohibit the use of approved products. An active ingredient is a compound that makes a pesticide • Keep pesticides out of the reach of children. The Quebec Pesticides Management Code has been in effect effective. It may act on insects (insecticide), weeds (herbicide), since April 2003. fungal diseases (fungicide), mites (acaricide) or molluscs (molluscicide), etc. To find out what active ingredient a product For their part, municipalities may pass more stringent by-laws, contains, look on the label after the “guarantee.” mainly governing pesticide usage in urban areas. Montréal’s n y t

By-law concerning pesticide use (04-041) was adopted s d l o in April 2004. G s e u q c a J : s n o i t a r t s u l l I Active ingredient Target organisms Application Precautions and how it works (not a complete list) FUNGICIDE-ACARICIDE Sulphur Black spot • Mites • Powdery mildew • Use as a preventive or as soon as symptoms appear. May be toxic to some plants, including cucumbers (Cucumis sativus ), squash (Cucurbita spp.), Rust • Scab • Depending on the formulation, dust or spray onto plants. Shake the sprayer well before and during treatment. Boston ferns (Nephrolepis exaltata 'Bostoniensis '), melons ( Citrullus lanatus , Cucumis melo ), Preventive Allow at least 30 days between the application of sulphur and treatment with mineral oil (horticultural oil). some varieties of pears (Pyrus spp.) and grapes (Vitis spp.). Contact Do not use at temperatures over 24°C. FUNGICIDE-ACARICIDE-INSECTICIDE Calcium sulphide Aphids • Black knot • Black spot • Coat all parts of the plants to be treated thoroughly, to the point where the product drips off. When applied during the growing season, may cause the foliage of some species such as plums (Prunus spp.) or calcium polysulphide Downy mildew • Mites • May be applied during dormancy in combination with mineral oil (horticultural oil). and some varieties of apples (Malus spp.) to turn yellow and drop off. (lime sulphur) Powdery mildew • Rust • During the growing season, allow at least 30 days between an application of May stain some surfaces, including painted wood, brick and stone. Scab • Scale calcium sulphide and treatment with mineral oil. Preventive Apply when temperatures are below 27°C, in the early morning or late afternoon or evening. Contact HERBICIDE Acetic acid Black medic (Medicago lupulina ) In spring or early summer, on warm, sunny days, spray the leaves of young weeds, coating the entire plant. Apply only to undesirable plants, as it is not selective. Chickweed (Stellaria media ) In a border or on a lawn, spray it directly on weeds and avoid contact with other plants. May damage some metal surfaces or lawn furniture. Contact Dandelion (Taraxacum officinale ) Repeat applications may be necessary to kill perennial or large weeds. Lamb’s quarters (Chenopodium album ) Plantain ( Plantago major ) Ragweed (Ambrosia artemisiifolia ) Corn gluten meal Dandelion (Taraxacum officinale ) Apply on established lawns in either early spring (May) or late summer (mid-August) before weed seeds germinate. Should not be applied to a newly seeded lawn, because it prevents grass seed from germinating. Large crabgrass (Digitaria sanguinalis ) Apply when the soil is moist. If it does not rain within 48 hours of applying the pesticide, water the lawn. Acts over a period of approximately 5 to 8 weeks. Germination inhibitor Smooth crabgrass (Digitaria ischaemum ) When fertilizing your lawn, keep in mind that corn gluten meal is high in nitrogen (nearly 10%). Mixture of capric and Chickweed ( Stellaria media ) Spray the leaves of young weeds in the spring or early summer. Apply only to undesirable plants, as it is not selective. pelargonic acids (fatty acids) Lamb's quarters ( Chenopodium album ) Cover the entire plant, without run-off. May leave white residue on some brick or concrete surfaces. Mustard ( Sinapis arvensis ) Do not apply if rain is forecast. These deposits will disappear within a few weeks. Contact Plantain ( Plantago major ) Wait three days after applying the herbicide before planting or seeding. Redroot pigweed ( Amaranthus retroflexus ) Repeat applications may be necessary to kill perennial or large weeds. Herbicidal soap Algae • Lichen • Liverworts • Moss On structures (roofs, wood framing, sidewalks, etc.), spray on enough to thoroughly wet all surfaces to be treated. The pesticide should be applied only to target organisms, as it is not selective. (potassium salts of fatty acids) On lawns, wet the moss and surrounding lawn before applying the product. May leave white residue on some brick or concrete surfaces. Thirty minutes after treatment, rinse the treated area. These deposits will disappear within a few weeks. Contact Reseed bare patches on lawns. INSECTICIDE Bacillus thuringiensis ssp. Cabbage worms • Gypsy moths • Specific to some species of caterpillars. Has no effect on adult insects (moths and butterflies). Should be kept in a cool place (between 4° and 15°C) to maintain its effectiveness, kurstaki (Btk) Oblique-banded leaf rollers • Spray on leaves, covering them thoroughly, without run-off. and used within 12 to 24 months of the manufacturing date. Tent caterpillars • Tomato hornworms Use in the early stages of an infestation, when young larvae are feeding actively. Ingestion Delay treatment if rain is forecast. Borax or boric acid Ants • Earwigs Depending on the formulation, spread a thin layer of powder or a few drops of the liquid Some products may contain peanut butter, and may be hazardous for people with allergies. or place traps along insect routes or near ant nests. Avoid applying powder or liquid formulations near plant roots. Ingestion Avoid using powder formulations in damp or wet locations. Can cause plants to dry out and/or interfere with photosynthesis. INSECTICIDE-ACARICIDE Mineral oil Aphids • Mites • Scale• Coat all plant parts thoroughly with the solution, to the point that it drips off. Should not be applied if there is a risk of frost or rain within 24 hours, during very humid weather, (horticultural oil) Whiteflies When plants are dormant, may be used in combination with calcium sulphide or calcium polysulphide. to plants suffering from drought, or on very hot days. During the growing season, allow at least 30 days between an application of May be toxic to some plants, including hickories ( Carya spp.), sugar maples ( Acer saccharum ), Contact mineral oil and treatment with lime sulphur or sulphur. Japanese maples ( Acer palmatum ), beeches ( Fagus spp.), hollies ( Ilex spp.), some apple varieties ( Malus spp.), Asphyxiant Ideally, the product should be sprayed on in the morning, to allow time for it to dry. walnuts ( Juglans spp.) and Douglas firs ( Pseudotsuga menziesii ). May discolour the needles of conifers with bluish foliage. New shoots will be a normal colour, however.

Insecticidal soap Aphids • Earwigs • Mites• Spray directly onto pests or affected plant parts (stems, leaves). May be toxic to some plants, including nasturtiums ( Tropaeolum spp.), ferns, impatiens ( Impatiens spp.) (potassium or alkanolamine salts) Scale • Whiteflies Apply early in the morning or evening or on a cloudy day. and sweet peas ( Lathyrus odoratus ). Do not apply on very windy days. Not effective once dry. To minimize the risk of phytotoxicity, it is best not to apply the product in full sun or to plants subject to stress (drought, extreme heat, etc.) Contact Not selective; may harm beneficial garden organisms. INSECTICIDE-MOLLUSCICIDE Silicon dioxide Ants • Earwigs • Apply during dry weather to pests or to spots that they frequent. Not selective; may harm beneficial garden organisms. (diatomaceous earth) Potato beetles • Slugs May also be sprinkled on leaves (avoiding flowers) or on the soil (without working it in) around the base of plants. Contact MOLLUSCICIDE Ferric phosphate Slugs • Snails Spread around the base of affected plants. Moisten the soil, without soaking it, before applying the product. Ingestion Apply the product in the evening, because slugs and snails are active mainly at night and early in the morning.